1. Field of the Invention
The present invention relates to a fastening member which is adapted to be employed in a siding work for fastening building boards such as ceramic siding boards to the side of a building frame.
2. Description of the Related Arts
As an exterior finish work of a building, a board siding work for attaching ceramic siding boards (building boards) to the side of a building frame is usually performed.
For example, as shown in FIGS. 5 and 6, in the case of wood frame construction (two-by-four construction) for example, a framework 1 is assembled at first, and after an underlayment 2 such as a plywood and a moisture permeable waterproofing sheet as desired is attached to the framework 1, ceramic building boards 40 are horizontally fastened via the underlayment 2 to the framework 1 by taking advantage of the studs 3 of the framework 1.
In this case, a first building board 40 to be disposed at the lowest portion of the framework 1 is horizontally placed at first to the framework 1 and fastened thereto using nails 4 by taking advantage of studs 3. Then, a second building board 40 to be fastened over the first building board 40 is horizontally placed with the lower rabbeted horizontal edge 40a of the second siding board being fitted over or engaged with the upper rabbeted horizontal edge 40b of the first building board 40, and then fastened to the studs 3 in the same manner as illustrated above using nails 4. Since the head 4a of the nail 4 employed in fastening the building board 40 is exposed in this case, thus deteriorating the external appearance or design of the finish, a coating coverage is usually subsequently applied to such an exposed head portion of the nails 4. Further, there is also a possibility that the building boards 40 may be damaged due to the nailing work.
With a view to overcome the aforementioned problems, there is also known a method of fastening building boards to the framework of a building frame by making use of a fastening member which is exclusively designed for the fastening. FIG. 8 illustrates one example of such a fastening member (Japanese Patent Unexamined Publication H10-2089). This fastening member 30 comprises a substrate 31 provided with an upstanding portion 31a extended rearward from the upper edge thereof and with an upstanding portion 31b extended rearward from the lower edge thereof, a concave portion 35 depressed rearward from the substrate 31 and having a peripheral wall 35a, a bottom 35b and an opening 35c formed in the bottom 35b for allowing a screw (a fixing member) to be screwed therein, and an engaging portion 33 which is formed contiguous to the distal end of the horizontal portion 32 extending forward from the substrate 31. In this case, the upstanding portion 31a extending from the upper edge of substrate 31 is extended obliquely upward and provided with openings 34b for driving a nail (a fixing member).
The method of fastening the building board 40 shown in FIG. 7 by making use of this fastening member 30 can be performed as explained below. In this case, all four sides of the building board 40 are respectively formed into a tongue portion for forming a shiplap joint. Specifically, the overlying tongue portion is formed at two sides thereof, i.e. a left side region extending from the left edge to a vicinity of the inner surface thereof and a lower side region extending from the lower edge to the inner surface thereof. The overlying tongue portion is consisted of an overlying tongue pattern-forming portion 41 forming the surface of board and a V-shaped groove portion 43 formed on the rear side, both portions being adapted to be piled on the underlying tongue portion. The specific configuration of the V-shaped groove portion 43 is formed such that can be engaged with the engaging portion of the fastening member to be employed.
On the other hand, the underlying tongue portion is formed at the remaining two sides thereof, i.e. a right side region extending from the pattern-forming right side edge to the vicinity of the outer side thereof and an upper side region extending from the pattern-forming upper edge to the outer side thereof. These two sides are respectively formed into an underlying tongue engaging portion 44 for receiving the overlying tongue pattern-forming portion 41 which is designed to be piled on the underlying tongue portion. Further, the specific configuration of latter underlying tongue portion is formed obliquely so as to be engaged with the engaging portion of the fastening member to be employed. Additionally, a caulking material 45 is adhered on the flat surface of both underlying tongue portions.
First of all, as shown in FIG. 9, the lower building board 40B is horizontally fastened. Then, the fastening member 30 is contacted with the studs 3 in such a manner that the lower portion of the engaging portion 33 of the fastening member 30 is engaged with the underlying tongue engaging portion 44 of the building board 40B. Then, a screw 5c (fixing member) is screwed into the studs 3 through the opening 35c, or a screw 5a (fixing member) is screwed into there through the opening 34a, or a nail (fixing member) is driven into there through the opening 34b, thereby fixing the fastening member 30 to the framework of a building.
Then, the V-shaped groove portion 43 of the next upper building board 40A is engaged with the upper side of the engaging portion 33 of the fastening member 30 that has been fixed in advance to the framework, thereby horizontally positioning this upper building board 40A along the studs 3. Then, in the same manner as described above, the next fastening member 30 is engaged with the underlying tongue engaging portion 44 of the building board 40A, and then, fixed to the studs 3 by making use of screws or nails. Thereafter, the same work as described above are repeated to attach the building boards 40 horizontally and in multistage to the side of a building frame, thereby accomplishing a decorative external sidewall.
When an underlying member (the studs 3) to which the aforementioned fastening member 30 is to be fixed is formed of a wooden member, the fixing member (nail) 5b can be inserted into the opening 34b formed in the obliquely extended upper upstanding portion 31a and driven obliquely downward into the studs 3, thereby fixing the fastening member 30 thereto. On this occasion, a component force directed downward is acted on the fastening member 30 to thereby push it downward. As a result, the fastening member 30 is caused to be positioned and fixed so as to enable it to firmly hold the building board 40B without leaving any gap between the building board 40B and the fastening member 30. However, when an underlying member (the studs 3) to which the aforementioned fastening member 30 is to be fixed is formed of a steel frame, the fastening member 30 is usually fixed by the screw 5a (fixing member) using the opening 34a, or fixed by the screw 5c (fixing member) using the opening 35c, in that case, the screwing into the steel frame is horizontal, because it is impossible to obliquely screwing the fixing member such as screw into the steel frame by making use of a power tool.
When the fixing member 5a is horizontally screwed into the steel frame from the opening 34a formed in the contacting portion 31d, it is impossible to enable a downwardly directed component force to be acted on the fastening member 30. Further, the plan view of a portion between the peripheral wall 35a constituting a cone-shaped concave portion 35 and the bottom 35b of the concave portion 35 is circular in general, and further, with a view to smoothing the screwing work, the minimum diameter of the concave portion 35 is made larger than the diameter of the diametrically large head portion 5d of fixing member 5c so as to prevent the head portion 5d of fixing member 5c from being contacted with the peripheral wall 35a on the occasion of screwing a screw as shown in FIG. 9. Therefore, even though the screwing work can be performed smoothly, it is impossible, when the fixing members 5c is horizontally screwed into the steel frame from the opening 35c formed in the concave portion 35, to enable a downwardly directed component force to be acted on the fastening member 30 as in the case where the fixing member (nail) 5b is driven obliquely downward into the underlying member.
Therefore, the fastening member 30 may be caused to float on the occasion of fixing it after it has been once positioned in place, because of a fairly large vibration generating from a power tool to be employed in the screwing work. When such a floating of the fastening member 30 is caused to generate, the fastening state between the fastening member 30 and the lower building board 40B becomes undesirably loosened, thus necessitating the worker to take a careful attention in the fastening work of the fastening member 30.
Therefore, an object of the present invention is to overcome aforementioned problems that may be encountered in the case of the conventional fastening member, and more specifically, to provide a fastening member which enables a downwardly directed component force to be acted on the fastening member at the final stage of screw-fixing the fastening member to an underlying member, thereby making it possible to push the lower building board (siding board) downward and to ensure a strongly fastened state of the building board.
With a view to realize the aforementioned objects, the present invention provides a fastening member which comprises; a substrate provided with an upstanding portion extended rearward from the upper edge thereof and with an upstanding portion extended rearward from the lower edge thereof; a concave portion depressed rearward from the substrate for fixing the fastening member to the building frame and having an inner wall, a bottom and an opening formed in the bottom for allowing a fixing member to pass therethrough; a horizontal portion extending forward from the substrate; and an engaging portion which is formed contiguous to the distal end of the horizontal portion; wherein said inner wall of the concave portion is provided at a lower wall portion thereof with an obliquely projected portion which enables a component force directed downward to be acted via the fastening member on an lower building board which is held below said horizontal portion by allowing said obliquely projected portion to be contacted with a diametrically large head portion of the fixing member at a final stage of fixing the fixing member to the side of a building frame on an occasion of fixing the fixing member to a post or a stud of a building frame through said opening formed in said bottom.
According to the fastening member of the present invention which is constructed as explained above, even if a fixing member such as screw is horizontally screwed into a post or a stud of a building frame by making use of a power tool, it is possible to give a downwardly directed component force to the fastening member through the aforementioned obliquely projected portion. Further, the fixing member functions as a substantial steady point, the fastening member is ultimately left remained in a downwardly urged state. As a result, the fixing member would not be inadvertently floated up by the vibration to be generated on the occasion of screwing the fixing member, and at the same time, building boards can be firmly fastened by the fastening member. The inner wall of the concave portion is configured into a cylindrical inner wall as a whole, and the obliquely projected portion may be a projection formed at a lower end portion of the cylindrical inner wall which is located in the vicinity of the bottom of the concave portion. Alternatively, the inner wall of the concave portion is configured into a conical inner wall as a whole, and the obliquely projected portion may be a lower portion thereof whose inclination angle is partially altered. Either of these configurations would be capable of achieving the object aimed at by the present invention.
Additionally, when the fastening member of the present invention is employed, the building boards can be firmly joined together with each other, thereby making it possible to effectively inhibit the generation of disengagement between the building boards, thus bringing about a secondary effect of preventing the generation of leakage of water through a gap between the building boards thus joined.